问题补充:
Be careful _too fast, or there _be an accident.
A. not to drive; must
B. to not drive; may
C. not drive; must
D. not to drive; may
答案:
A. not to drive; must
B. to not drive; may
C. not drive; must
(答案→)D. not to drive; may
解析:本题的含义是当心开车不要开得太快,否则可能会发生交通事故。Be careful not to do表示当心不要做某事的意思,动词不定式的否定形式在to do前加not,may表示可能性或许的意思,故本题选D。